Everything You Need to Know About Cold-Climate Heat Pumps

What challenges do heat pumps face in cold climates, historically?

For many homeowners, heat pumps have presented a perfect solution for optimizing home comfort, improving energy-efficiency and reducing carbon emissions. But for those located in regions with colder climates, hesitation surrounding the efficacy of this new technology in freezing temperatures has slowed adoption.

To understand where this hesitation comes from, it’s helpful to first understand how heat pumps work. Heat pumps warm your home in the winter by extracting heat from the air, ground or water outside and transferring it inside. Heat is carried by something called a refrigerant – a substance that begins as a cold liquid and shifts into a warm gas as it absorbs that outdoor air. This warm gas is then compressed to reach peak levels of heat, before being released into the home.

This process uses much less energy than traditional combustion systems, like furnaces, which generate heat themselves instead of moving it from one place to another. When operating within cold or freezing temperatures, however, accessing and extracting that heat from outside can be trickier than it would be within milder climates.

So, while successful operation has been achieved, the threat of reduced efficiency or increased stress on the unit has put many homeowners in colder regions off from heat pumps – leading ownership rates to be 6 to 7 times higher in the Southeast U.S. than in the Upper Midwest, according to Bosch’s market research.

Where did this solution come from?

The benefits of heat pumps make solving the cold climate issue a goal worth fighting for. Bosch has spent years pushing the boundaries of existing heat pump technology in the quest to develop a solution capable of meeting this need – and in 2023, the U.S. Department of Energy (DOE) accelerated this mission with the Residential Cold Climate Heat Pump Challenge.

Bosch and other HVAC equipment manufacturers participating in the DOE’s challenge were tasked with developing a heat pump system that would not only operate within colder climates but provide the same level of comfort and efficiency enjoyed by those in warmer regions who use the technology.

Bosch rose to the occasion with the IDS Ultra, and after five weeks of extensive testing in an ice-cold lab at the DOE’s Oak Ridge National Laboratory in Tennessee, it became the first product of this challenge to reach the market.

…and it won’t run more than it should to counteract the cold temperatures?

Nope. The IDS Ultra uses the same inverter compressor technology Bosch is known for to adjust operating capacity as needed, so your system never works harder than it needs to.

In fact, the IDS Ultra is so efficient that it’s ENERGY STAR-rated – a certification applied to units considered to perform better and more efficiently than standard alternatives. The IDS Ultra is an Energy Star V6.1 Cold Climate Certified heat pump.

Anything else I should know about the IDS Ultra?

It’s the first Bosch unit to use R-454B, an A2L class refrigerant that boasts reduced contributions to global warming when compared to other leading refrigerants.

Beginning in 2025, Bosch will begin producing its entire product line with this refrigerant, in line with the Environmental Protection Agency (EPA)’s AIM Act.

For more information on the IDS Ultra, be sure to check out this video and visit the IDS Ultra product page. And if you’re a homeowner within a colder climate who’s ready to unlock greater energy-efficiency and improved home comfort, contact a Bosch Home Comfort PRO today to begin planning for your very own IDS Ultra installation.